Ender S1 bed leveling tool

I finally get bed leveling control of my Ender S1 Pro with this tool and:
- a level micrometer (like this one: Aliexpress urly.it/3tr7j)
- nr. 5 M5 screws

I suggest moving the head of the micrometer directly on the bed (without the bed sheet) (see the photos).

To keep the calibration I take advantage of these clips:
https://www.thingiverse.com/thing:5858852/files
To avoid losing position, my advice is to keep the clip in contact with the bed by turning the bed knob clockwise.

I've tested this solution and the printer keeps the bed leveling over the time.